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Effects of electron-phonon coupling on absorption spectrum: K edge of hexagonal boron nitride
- Source :
- Physical Review B. 98
- Publication Year :
- 2018
- Publisher :
- American Physical Society (APS), 2018.
-
Abstract
- A detailed analysis of the theoretical x-ray absorption near-edge structures (XANES) for the boron and nitrogen $K$ edge in hexagonal boron nitride ($h$-BN) employing density-functional theory calculations is presented. The supercell core-hole method and the Bethe-Salpeter equation are used for the description of electron-hole interactions. The calculations are carried out with two different codes, the vasp and the wien2k codes, employing the projector augmented-wave and the full-potential linear augmented-plane-wave methods, respectively. We find close agreement between spectra obtained from the two codes and between calculations using the supercell core-hole method and the Bethe-Salpeter approach. All our calculations, as well as previous calculations using the ground-state structure, yield a single $2{p}_{{\ensuremath{\sigma}}^{*}}$ peak in the boron $K$-edge spectrum and hence fail to describe the experimental double-peak structure. We find that the inclusion of electron-phonon interactions is crucial to obtain the experimentally observed double-peak structure. We include these effects fully parameter free and ab initio using a one-shot sampling method and obtain excellent agreement with experiment.
- Subjects :
- Materials science
Absorption spectroscopy
Ab initio
chemistry.chemical_element
02 engineering and technology
021001 nanoscience & nanotechnology
01 natural sciences
Molecular physics
XANES
WIEN2k
Condensed Matter::Materials Science
K-edge
chemistry
0103 physical sciences
Supercell (crystal)
Absorption (logic)
010306 general physics
0210 nano-technology
Boron
Subjects
Details
- ISSN :
- 24699969 and 24699950
- Volume :
- 98
- Database :
- OpenAIRE
- Journal :
- Physical Review B
- Accession number :
- edsair.doi...........0c48af50927fee4ca11db8383f7753aa